Abstract

Background: Low birth weight (LBW) remains a major public health problem in developing
countries, but is only one measure of size at birth. Others include small-for-gestational-age
(SGA) and low ponderal index (PI). The objectives of the thesis were: to estimate the
prevalence of LBW, SGA and low PI in a cohort of Nepalese infants; to identify risk factors for
small size, and to investigate whether prediction models were useful for screening; and to
assess the effects of size at birth on subsequent outcomes.
Methods: Mothers enrolled in a prospective trial were followed through pregnancy and
delivery. Child anthropometry was collected at birth and at two years of age. A range of indices
of size at birth were described. Multivariable regression models were developed to predict
them, and their associations with subsequent outcomes.
Results: There was a high prevalence of LBW (25%), SGA (55%) and low PI (70%) at birth.
None of the prediction models for size at birth was particularly good, the strongest being for
birth weight (R2=33%). Common predictors were parity, pre-pregnancy weight, gestational
weight gain, gestational duration and infant sex. LBW was associated with neonatal (OR 3.5,
95% CI 1.4-8.9), infant (3.6, 1.6-7.9) and young child (3.7, 1.7-7.8) mortality, and stunting (3.4,
2.2-5.3), wasting (2.9, 1.5-5.6) and underweight (3.7, 2.5-5.5) at two years of age.
Discussion: In southern Nepal, many newborn infants were classified as small, and most were
disproportionate. The modifiable risks for small size at birth were few, even though it was
associated with mortality and size in childhood.
Conclusion: The previously undescribed disproportionate majority of Nepalese infants is
worrying for public health. However, measurement of birth weight is not yet routine and it seems better to recommend LBW as a single risk measure than to add new and more
complicated activities.

Type:

Thesis
(Doctoral)

Title:

Size at birth: an examination of meaning and usefulness.
A prospective study of a cohort of infants born in Nepal